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I assume this is one specific assembly or just any assembly of parts? In general, it just works with no problem. So if it is any parts, it's likely something about the way you are doing. If its specific parts, it's likely geometry related.
Are the parts barely intersecting or is the shapes extremely complicated? Sometimes when the parts are complicated, an interference will just say "unable to calculate interfence" or something similar.
Also, if parts are surface models (or one is), volume can't be calculated.